Drug-resistant tuberculosis in eastern Europe and central Asia: a time-series analysis of routine surveillance data

Abstract

Background: Among all WHO regions, the WHO European Region has the highest proportion of drug-resistant tuberculosis among new and retreated cases. The 18 high-priority countries in eastern Europe and central Asia account for 85% of the tuberculosis incidence and more than 90% of drug-resistant tuberculosis cases emerging in the region. We aimed to analyse time-series trends in notification rates of drug-resistant tuberculosis among new tuberculosis cases in the 18 high-priority countries in the WHO European Region.

Methods: We used country data stored in WHO's global tuberculosis database. For each country, we calculated annual notification rates per 100 000 population of new tuberculosis cases and of drug-resistant tuberculosis among new cases reported from Jan 1, 2000, to Dec 31, 2017. We computed annual percentage changes of notification rates and identified time-points of significant change in trends using the joinpoint regression method.

Findings: All 17 countries with data (no data available from Turkmenistan) showed a significant decline in new tuberculosis notification rates in the most recent years since the last joinpoint if one was identified. Notification rates of drug-resistant tuberculosis showed diverse trends, with substantial year-to-year variation. In the most recent years, notification rates of drug-resistant tuberculosis among new tuberculosis cases were decreasing in two countries (Estonia and Latvia), increasing in eight countries (Azerbaijan, Kyrgyzstan, Moldova [Republic of Moldova], Romania, Russia [Russian Federation], Tajikistan, Ukraine, and Uzbekistan), and stable in seven countries (Armenia, Belarus, Bulgaria, Georgia, Kazakhstan, Lithuania, and Turkey).

Interpretation: Our findings suggest that countries in the WHO European Region are more successful in controlling drug-susceptible tuberculosis than drug-resistant forms, and as a result, the proportion of drug-resistant strains among newly notified patients with tuberculosis is increasing in many settings. Two countries showed that it is possible to decrease incidence of both drug-susceptible and drug-resistant tuberculosis. If no additional efforts are made in prevention and care of patients with drug-resistant tuberculosis, further decline of the tuberculosis burden will be halted. Further studies are needed to investigate the success stories and document the most effective interventions to reach the target to end tuberculosis by 2030.

Funding: United States Agency for International Development.